Knife sharpening mechanism



. 1935- H. STUKART 2,052,365

KNIFE SHARPENING MECHANISM Filed June 9, 1934 -|NVENTO-R 52 HENDRIK STUKART OF BY M KNIFE CUTTING EDGE g Patented Aug. 25, 1936 KNIFE 'SHARPENING MECHANISM Hendrik Stukart, LaPorte, Ind, assignorito U. S. Slicing Machine Company, .La vIorte, Ind., a

corporation of Indiana Applicationalune 9, 1934, SerialNo. 729,749

1'0'Claims. (Cl."1--24'8) This invention relates .to'. slicing machines; and particularly to sharpening .mechanzism therefor. The primary object of .theinvention is to pro-- vide a new and improved sharpening mechanism :for slicingmachine knives of thecircularrotary type.

'Another object of the invention is to provide sharpeningv mechanism for slicing machine: knives whereby a pair of sharpening stones comprising a-grindingstone and a bnrrlremoving stone are resiliently mountedand urged in a predetermined direction whereby the grinding. stones. have a resilient grinding action on theknife; thestones being maintained in a predetermined position by stop elements and having new. and improved means for permitting quick andinstant removal of the'stones.

Numerous other objects and advantages will be apparent throughout the progressof the following specification.

The accompanying drawing illustratesa selected embodiment of the invention and the views therein are as follows:

Fig. 1 is a detail vertical sectional viewthrough the improved sharpening mechanism'sho-wing the same out of contact with the knife but moved to grinding position as regards the knife.

Fig. 2 is a plan section thereof jtaken substantially along the line 2-2 of Fig. 1.

Fig. 3 is a detail elevation showing the position of the grinding stones as setforth in.Fig. 11looking from the right toward the left of the machine.

The slicing machine upon whichthe sharpening mechanism cooperates is of the type shown in the copending applications, SerialNo. 718,583, filed April 2, 1934, and Serial No.t718,584,.filed April 2, 1934. In the1first mentioned copending application sharpeningmechanism is disclosed in combination with a particular type of guard plate. In the second mentioned copending application sharpening mechanism of a similar type is shown and claimed but several of the features of the mechanism disclosedin this application are not disclosed; the presentsharpening mechanismv relating particularly to the specific arrangement and construction of the. grinding stone mountings and the casing, whereby the housing, when turned, permits the stones to be freed, allowing them to move toward each otherzin theiraxes of rotation.

The slicing machine upon whichthe present sharpening mechanism is mounted and which is shown and disclosedin the aforesaidcopending application, SerialNo. 718,584, filed April 2, .1934, comprises a knife l6 which is rotatably mounted ona knife supporting bracket H. The supporting .brackettl may comprise a part of the housing for the knife or the knife guard. A knife guardas shown in the aforesaid copending application, Serial No. 718,584, filed April 2, 1934, is 5 adapted to extend about the periphery of the knife at the side opposite the operator. 7 A vertical spindle I8 is slidably supported in the supportingbracket memberl'l and carries a housing I9 which is pivotally mounted thereon, being 10 held by a screw 2D. The housing l9 comprises a body 2! and a portion 22 which may be pivotally attached at 23 to the housing by means of .a hinge connection 24. A sharpener stone 25 is arranged on one side of the knife l6, Figs. 2 and .3, and constitutes the grinding stone. A second stone 26 is arranged on the other side of the knifeand constitutes the burr removing stone.

Thelsharpener stone 25 is mounted ona shoulder spindle "21 and'held thereto'by a screw"2'8.; The spindle '21 is rotatably assembled in a sleeve 29 which'isaxially adjustable in a bearing 3!] in the housing. The bearing '30 is removable from the spindle '13 but is rigidlyconnected thereto by a set screw (not shown). The spindle 21 is axially held in the sleeve 29 by a washer 3| and a screw 32. The burr removing stone 26 is fastened to a spindle 34 by a screw 35, Fig. 2, and this spindle is rotatably mounted in a sleeve 36 which is axially movable in a bearing 31.. The 30 bearing 31 is integrally connected to the bearing 30 by a connecting web 38. The spindle 34 is held against axial movement in the sleeve 36 by a washer 39 and a screw 39'.

The sleeve 29 has a smallerturned end providing a recess 40 in which there is mounted a spring 4| for urging the spindle 21 to the left, Fig. 2. Anti-friction bearings '42 are arranged between the spindle 2.1 and the sleeve 2.9.asclearly indicated in Fig. .2. A side wall of .the bearing is 40 provided with a longitudinal slot 43, and apin 44 which is fastened to the sleeve 29 protrudes outwardly through the slot 43. The pin 44 is adapted to abut against a stop pin 45 which is mounted on a supporting arm, 46 and extends 45 through an opening 141 formed in the housing body2l. The arm 46 is'made of spring material and normally tends to hold the stop pin 45 against thepin 44 as shown in Fig. 2. However, to remove the grinding stone 25, including the spindle 50 21. and the sleeve 29 from the bearing 30, the arm 46 is moved outwardly a predetermined distance to clear the stop pin 45 from the pin 44. .The spring arm 46 may be fastened in any convenient operable manner, such as bya fastening screw 48.

-'the end of their respective slots'43 and 52.

When it is desired to remove the grinding stone 25, including the spindle 2! and the sleeve 29, the housing cover 22 is swung on its pivot 23 and the spring arm 46 is moved outwardly to free the pin from the pin 44 at which time the assembly may be removed from the bearing 36.

The sleeve 36 has a smaller turned end providing a recess 49 in which there is mounted a spring 56 for urging the spindle 34 to the right, Fig. 2. Anti-friction bearings 5| are arranged between the sleeve 36 and the washer 39 as clearly indicated in Fig. 2. A side wall of the bearing 36 is provided with a longitudinal slot 52, and a pin 53 which is fastened to the sleeve 36, protrudes outwardly through the slot 52. The pin 53 is adapted to abut against a stop pin 54 which threadedly engages the casing, Fig. 2. The arm spring 56 normally urges the sleeve 36 to the right but is held from assuming that position normally by the stop pin 54.

The spring 4| therefore urges the grinding stone outwardly from the casing (to the left) but is prevented from doing so by the engagement of the pin 44 with the stop pin 45; while the spring 56 urges the burr removing stone 26 inwardly of the casing (to the right) but is prevented from doing so by the engagement of the pin 53 with the stop pin 54. The integral bearing which comprises the parts 36, 3'! and 38 is fixed to the shaft therefore tends to cause rotative movement of the housing relative to the integral bearing but this rotative movement is prevented by the pins 44 and 45, and the pins 53 and 54. This urging action causes the pins 44 and 53 to be seated in As previously mentioned, the casing I9 is pivotally connected to the spindle |8. Therefore when the casing I9 is manually rotated in a clockwise direction, Fig. 2. against the urging action of the spring 59, the springs 4| and 56 will move the grinding stones toward the cutting edge of the knife. The spring 59 tends to force the integral bearing 30, 31, 38 in a counterclockwise direction, but this urging action in a counterclockwise direction is limited by the pins 44 and 53 engaging the stop pins 45 and 54 respectively.

The vertical spindle I8 is slidably mounted in a boss 60 formed on the bracket |1, Fig. 1, and

the lower end of the shaft or spindle I8 is pro-' vided with oppositely disposed vertical grooves 6| which are adapted to be engaged by a set screw 62 having a knurled thumb piece 63. The end of the set screw 62 is provided with a smooth pilot end 64 which fits into the groove, whereby the spindle I8 is adapted to have vertical slidable movement in the opening in the boss 60 but is normally prevented from rotating by the engagement of the pilot 64 with either one of the grooves or slots 6 The spindle l8 has a reduced lower end as indicated at 65, the reduced portion being substantially the diameter as the distance between the grooves 6|. A knob 66 is formed on the bottom of the spindle I8, and this knob is substantially the samediameter as the normal -diameter of the spindle [8. The spindle there-' in Fig. 1.

fore is free to have vertical slidable movement in the boss 60, but is prevented from rotating by the engagement of the pilot 64 with a groove 6|. The spindle may be raised upwardly until the upper surface of the knob 66 engages the lower surface of the set screw 62. In this latter position the smooth pilot end 64 will be at the reduced diameter of the spindle at which time the spindle is free to be rotated. As shown, the sharpeningmechanism is in grinding position as regards the knife |6, but the normal idle position of the sharpening mechanism is removed 180", from the position shown in the figures or in the position shown in dotted lines When the sharpening mechanism is in its normal idle position, that is, away from the knife, the set screw 62 will engage one of the vertical slots 6|; but when the sharpening mechanism is rotated 180 to knife sharpening position, the set screw will engage the other groove 6| as shown in Fig. 2. In other words, the set screw engages one groove in idle position and engages the other groove in operating position when the shapening mechanism has been ro-' tated, 180, about its vertical axis. To rotate the spindle, however, the spindle must be raised upwardly until the reduced diameter is opposite the pilot 64 at which time the spindle can be turned until the other groove 6| is in position in respect to screw 62 when the spindle is again lowered to bring the mechanism into sharpening position relative to the knife. A set screw 61 threadedly engages a part of the boss 60 and engages the set screw 62 to hold the set screw 62 in its proper operative locked position and preventnnauthorized removal of the spindle |8..

To remove the spindle I8 from the boss 66, the set screw 61 is first unscrewed to release its engagement with the screw 62. The set screw 62 can be rotated to move pilot end v64 out of the path of the knob 66. The locking engagement of the set screw 61 with the set screw 62 may comprise a point on the end of the screw 61 engaging a groove provided in the set screw 62. A knurled nut 68, Fig. 1, threadedly engages the spindle I6 and rests upon the top of the boss 66. Rotation of the knurled nut 68 adjusts the sharpening mechanism vertically. A set screw 69 threadedly engaging the knurled nut 68 locks the knurled nut in adjusted position in respect to the shaft or spindle |8. The knurled nut 68 adjusts the housing and its encased sharpening mechanism vertically to compensate for wear of the knife.

The invention provides compact, efficient, sharpening mechanism which is normally removed from the knife but which is brought into proper position in respect to the knife upon rotation of When it is desired to bring the stones into contacting engagement with the knife, the housing I9, top of Fig 1, is given a clockwise twist or turn, which would appear as anti-clockwise in Fig. 2 because that is a view from below. This twist or turn causes no pressure to be exerted against the knife but merely compresses the spring 59 and moves the top pins 54 and 45 away from the pins 53 and 44, allowing the springs 4| and 50 to urge their respective stones into contacting engagement with the opposite sides of the knife. Both stones therefore are yieldingly urged into contacting or sharpening relationship with the knife by the springs arranged in the respective bearings. The grinding stone 25 can be freely and quickly replaced by manipulating the spring arm 46 to free the pin 44 from the stop pin 45. The pivotal engagement of the shield .or cover plate Zlipermits .free' and easy'accessto the interior'of. theicasingi'fi;

Changes maybe made in. the form, construct tion and arrangement of. the partswithoutdeparting from thespirit of theinvention orrsacrificingnany of thezadvantages, and the .right is hereby reserved to make alLsuch changes asfairly fall within the scope ofthe following claims.

a The invention. is hereby claimed asfo'llows:

1. In a 'slicing machine, having a rotary knife, sharpeningv mechanism therefor comprising. a. pair ,of sharpeners adapted. to. be arranged on opposite sides :of thesknife for straight line move ment to and from the knife, a bearing and a'resilien'tmounting forimoving each sharpener into engagement with the knife, a casing in which said bearing and sharpeners are arranged, said casing being mounted on a vertical spindle and adapted to have rotary movement in respect thereto, stop means mounted on the casing for arresting action of the resilient mounting, said stop means being removable from arresting position by rotary movement of the casing thereby permitting movement of the sharpener into sharpening engagement with the knife by the resilient mountings upon said rotary movement of the casing.

2. In a slicing machine having a rotary knife, a sharpening mechanism therefor comprising a pair of sharpeners arranged on opposite sides of the knife for straight line movement, a bearing for said sharpeners, a casing for housing the bearing and sharpeners, said casing adapted for rotation about a vertical support, resilient means for urging one sharpener toward the bearing and the other sharpener away from the bearing, said resilient means being normally restrained from moving the sharpeners into contacting relationship with the knife, said restraint being removed by rotation of the casing in a predetermined direction.

3. In a slicing machine having a rotary knife, a sharpening mechanism therefor comprising a pair of sharpeners arranged on opposite sides of the knife, a bearing for said sharpeners, a revolubly mounted casing for housing the bearing and sharpeners, said casing adapted to be manually rotated, springs urging one sharpener in one direction and the other sharpener in the opposite direction, stop pins for holding the sharpeners in a predetermined position, rotatable movement of the housing freeing the stop pins and permitting the springs to urge the sharpeners into sharpening engagement with the knife.

4. In a slicing machine having a rotary knife, a sharpening mechanism therefor comprising a pair of sharpeners arranged on opposite sides of the knife, a bearing for said sharpeners, a support, a casing rotatably mounted on the support and adapted for rotative movement in respect to the support, said casing housing the bearing and sharpeners, said bearing having slots therein, pins operatively connected to the sharpeners and extending through said slots, sharpener springs, and stop means engageable with said pins for limiting the movement of the first named pins, said stop pins being moved away from the first named pins upon rotative movement of the casing whereby the sharpener springs will move the sharpeners into contacting relationship with the knife.

5. In a slicing machine having a rotary knife, a sharpening mechanism therefor comprising a pair of! sharpeners arranged on opposite sides. of

the knife, a bearing for said sharpeners, a supsprings. urging one sharpener. in. one direction and the o'ther sharpener in the opposite direction, stop pins for holding the sharpeners in a predetermined position, rotatablemovement of therhou'sing on its support freeing the stop pins andpemnitting the springsto urge the sharpeners .into sharpening engagement with the knife, a revolubly mounted longitudinally slidable spindle lfor "said mechanism, and means for locking the spindle in predetermined positions.

6,. In aslicingrmachine having a rotary knife, a sharpening mechanism therefor comprising a pair of sharpeners arranged on opposite sides of the knife, a bearing for said sharpeners, a support, a casing rotatably mounted on said support and housing the bearing and sharpeners, said bearing having slots therein, pins operatively connected to the sharpeners and extending through said slots, sharpener springs, stop means engageable with said pins for limiting the movement of the first named pins, said stop pins being moved away from the first named pins upon rotative movement of the casing whereby the sharpener springs will move the sharpeners into contacting relationship with the knife, a revolubly mounted longitudinally slidable spindle for said mechanism, and means for locking the spindle in predetermined positions.

7. In a slicing machine having a rotary knife, a sharpening mechanism therefor comprising a pair of sharpeners arranged on opposite sides of the knife, a bearing for said sharpeners, a support, a casing adapted for rotative movement on the support for housing the bearing and sharpeners, said bearing having slots therein, pins operatively connected to the sharpeners and extending through said slots, sharpener springs, and stop means engageable with said pins for limiting the movement of the first named pins, said stop pins being moved away from the first named pins upon rotative movement of the casing whereby the sharpener springs will move the sharpeners into contacting relationship with the knife, said casing having a slot therein, one of said stop pins being hingedly connected to the casing and passing through said slot in the casmg.

8. In a slicing machine having a rotary knife, a sharpening mechanism therefor comprising a pair of sharpeners arranged on opposite sides of the knife, a bearing for said sharpeners, a support, a casing adapted for rotative movement on the support for housing the bearing and sharpeners, said bearing having slots therein, pins operatively connected to the sharpeners and extending through said slots, sharpener springs, stop means engageable with said pins for limiting the movement of the first named pins, said stop pins being moved away from the first named pins upon rotative movement of the casing whereby the sharpener springs will move the sharpeners into contacting relationship with the knife, a revolubly mounted longitudinally slidable spindle for said mechanism, and means for locking the spindle in predetermined positions, said casing having a slot therein, one of said stop pins being hingedly connected to the casing and passing through said slot in the casing.

9. In a slicing machine having a rotary knife,

a sharpening mechanism therefor comprising a pair of sharpeners arranged on opposite sides of the knife, a bearing for said Sharpeners, a revolubly casing for housing the bearing and sharpeners, springs urging one sharpener in one direction and the other sharpener in the opposite direction, stop pins for holding the sharpeners in a predetermined position, rotatable movement of the housing freeing the stop pins and permitting the springs to urge the sharpeners into sharpening engagement with the knife, a spindle for said casing, and a support for the spindle, said spindle being rotatable 180 on said support.

10. In a slicing machine having a rotary knife,

a sharpening mechanism therefor comprising a pair of Sharpeners arranged on opposite sides of the knife, a. bearing for said Sharpeners, a revolubly mounted casing for housing the bearing and Sharpeners, springs urging one sharpener in one direction and the other sharpener in the opposite direction, stop pins for holding the sharpeners in a predetermined position, rotatable movement of the housing freeing the stop pins and permitting the springs to urge the sharpeners into sharpening engagement with the knife, and a hinged cover on the casing to permit withdrawal of the sharpeners from one side of the casing.

HENDRIK STUKART. 

